LibWeb: Bring handling of anchor elements closer to spec

This commit moves the regular handling of links to the anchor elements'
activation behavior, and implements a few auxiliary algorithms as
defined by the HTML specification.

Note that certain things such as javascript links, fragments and opening
a new tab are still handled directly in EventHandler, but they have been
moved to handle_mouseup so that it behaves closer to how it would if it
was entirely up-to-spec.

1 files changed, 41 insertions, 0 deletions

diff --git a/Userland/Libraries/LibWeb/HTML/HTMLAnchorElement.cpp b/Userland/Libraries/LibWeb/HTML/HTMLAnchorElement.cpp
index 665b119027..3b2533fd13 100644
--- a/Userland/Libraries/LibWeb/HTML/HTMLAnchorElement.cpp
+++ b/Userland/Libraries/LibWeb/HTML/HTMLAnchorElement.cpp
@@ -11,6 +11,9 @@ namespace Web::HTML {
 HTMLAnchorElement::HTMLAnchorElement(DOM::Document& document, DOM::QualifiedName qualified_name)
     : HTMLElement(document, move(qualified_name))
 {
+    activation_behavior = [this](auto const& event) {
+        run_activation_behavior(event);
+    };
 }
 
 HTMLAnchorElement::~HTMLAnchorElement() = default;
@@ -33,4 +36,42 @@ void HTMLAnchorElement::set_hyperlink_element_utils_href(String href)
     set_attribute(HTML::AttributeNames::href, move(href));
 }
 
+void HTMLAnchorElement::run_activation_behavior(Web::DOM::Event const&)
+{
+    // The activation behavior of an a element element given an event event is:
+
+    // 1. If element has no href attribute, then return.
+    if (href().is_empty())
+        return;
+
+    // 2. Let hyperlinkSuffix be null.
+    Optional<String> hyperlink_suffix {};
+
+    // FIXME: 3. If event's target is an img with an ismap attribute
+    //        specified, then:
+    //   3.1. Let x and y be 0.
+    //
+    //   3.2. If event's isTrusted attribute is initialized to true, then
+    //   set x to the distance in CSS pixels from the left edge of the image
+    //   to the location of the click, and set y to the distance in CSS
+    //   pixels from the top edge of the image to the location of the click.
+    //
+    //   3.3. If x is negative, set x to 0.
+    //
+    //   3.4. If y is negative, set y to 0.
+    //
+    //   3.5. Set hyperlinkSuffix to the concatenation of U+003F (?), the
+    //   value of x expressed as a base-ten integer using ASCII digits,
+    //   U+002C (,), and the value of y expressed as a base-ten integer
+    //   using ASCII digits.
+
+    // FIXME: 4. If element has a download attribute, or if the user has
+    // expressed a preference to download the hyperlink, then download the
+    // hyperlink created by element given hyperlinkSuffix.
+
+    // 5. Otherwise, follow the hyperlink created by element given
+    // hyperlinkSuffix.
+    follow_the_hyperlink(hyperlink_suffix);
+}
+
 }